Aroma compositions containing cycloaliphatic crotonyl compounds

ABSTRACT

This invention relates to new aromatic compositions containing cycloaliphatic crotonyl compounds of the type of trans-2,4,4trimethyl-1-crotonyl-cyclohex-2-ene wherein the 3-position of the cyclohexene may contain a hydrogen or a lower alkyl. These compounds have been found to be excellent odoriferous agents for perfumes and other industries.

I Umted States Patent 1 [111 3,897,370 Klein July 29, 1975 AROMA COMPOSITIONS CONTAINING CYCLOALIPIIATIC CROTONYL [56] References Cited COMPOUNDS UNITED STATES PATENTS [75] Inventor: Erich Klein, Holzminden, Germany 2,636,052 4/1953 Grutter 260/587 [73] Assignee: Dragoco Spezialfabrik Konzent rierte Riech'und Aromasmfie Gerberding 315301171 9 1970 Heckert I. 260/587 & Co. GmbH, Holzminden, Germany Filed: Nov. 3, 1972 Appl. No.: 303,352

Related US. Application Data Division of Ser. No. 146,554, May 24, 1971, Pat. No. 3,822,315,

Foreign Application Priority Data Apr. 26, 1971 Germany 2120413 US. Cl. 252/522; 426/175; 426/222 Int. Cl. A6lk 7/00; Cl lb 9/00 Field of Search 252/522; 260/586 R, 587

Primary ExaminerAlbert T. Meyers Assistant Examiner-A. P. Fagelson Attorney, Agent, or Firm-Steinberg and Blake [57] ABSTRACT This invention relates to new aromatic compositions containing cycloaliphatic crotonyl compounds of the type of trans-2,4,4-trimethyl-l-crotonyl-cyclohex- 2-ene wherein the 3-position of the cyclohexene may contain a hydrogen or a lower alkyl. These compounds have been found to be excellent odoriferous agents for perfumes and other industries.

3 Claims, No Drawings AROMA COMPOSITIONS CONTAINING CYCLOALIPHATIC CROTONYL COMPOUNDS CROSS REFERENCE TO RELATED APPLICATION This application is a divisional of my copending application Ser. No. 146,554, filed May 24, 1971, for Cycloaliphatic Crotonyl Compounds, now U.S. Pat. No. 3,822,315.

BACKGROUND OF THE INVENTION The invention relates generally to 3-hydrogen or lower alkyl-2,4,4-trimethyl- 1 -crotony1-cyc1ohex-2-ene compounds which have been found to be highly effective in enriching odors or natural perfumes and of artificial aromas. The art is always seeking new substances which can be used for this purpose.

SUMMARY OF THE INVENTION Generally speaking, in accordance with the invention, there is provided the use of new compounds of the type of 3-hydrogen or lower alkyl-2,4,4-trimethyl-lcrotonyl-cyclohex-Z-ene compounds as odoriferous agents, for example, as additives to perfumes and the like.

It is accordingly a primary object of the present invention to provide for the use of these compounds in the perfume and aroma industries and for related purposes.

Other objects and advantages of the present invention will be apparent from a further reading of the specification and of the appended claims.

With the above and other objects in view, the present invention mainly comprises artificial aroma compositions such as perfume compositions having incorporated therein an unsaturated ketone, of the formula:

CIA,

C. II

wherein R may be hydrogen or lower alkyl, preferably CH3 OI C2H5.

The following are the three preferred compounds of the invention:

trans-2,4,4-trimethy1- l -crotonyl-cyclohex-2-ene, i.e.

the above compound wherein R H; trans-2 ,3 ,4,4-tetramethy1-1-crotonyl-cyclohex-2-ene,

i.e. R CH and trans-2 ,4,4-trimethy1-3-ethyll -crotonyl-cyc1ohex- 2-ene, i.e. R C H It has been found that the new compounds of Formula I above, are particularly useful in the production of perfumes and artificial aromas. Thus, by the addition of one of these new crotonyl compounds to flower perfumes, a surprisingly natural odor impression is achieved and the odor intensity is considerably increased.

In the production of artificial aromas, the new compounds of the invention develop very natural fruit-like and increased wine-like and fresh flower-like nuances. The amounts in which the new crotonyl compounds can be used depends upon the desired effect and can be varied within very wide limits. Thus, for example, in the perfume field amounts of 0.03-10% can be used, whereas in the field of artificial aromas amounts of between about 0.515% are suitable. Each expert is in a position, depending upon the desired effect, to select a concentration for his purposes.

The production of the new crotonyl compounds of Formula I can be carried out by reacting an unsaturated cyclic hydrocarbon of the formula:

wherein R has the same definition as above, in the presence of a Lewis acid, such as B1 SnCl, or ZnCl with crotonic anhydride (crotonic acid anhydride). An acylation of the unsaturated hydrocarbon of Formula 11 proceeds with displacement of the double bond in the cyclohexene ring to directly produce the crotonyl compound of Formula I above. The surprisingly uniform course of the reaction in a single stage proceeds without a solvent at temperatures between about 0C and 60C, most preferably at a temperature of about 20C.

The compounds which are used as starting substances for the method of the present invention are known compounds which are commercially available or are agents which are known in the literature and can be easily produced according to known methods. The new compounds of the invention enrich in a most valuable manner the choice of additives for perfumes and artificial aromas.

DESCRIPTION OF PREFERRED EMBODIMENTS The invention is further illustrated below by the examples which follow. The scope of the invention is not, however, meant to be limited to the specific details of the examples.

EXAMPLE 1 Production of trans-2,4,4-trimethy1- l -crotony1-cyclohex-2-ene 62 g of l,5,5-trimethylcyclohex-l-ene are added dropwise under stirring at a temperature of 20C to a mixture of 77 g of crotonic anhydride and 10 g of zinc chloride. After the end of the addition the reaction mixture is stirred for 8 hours at 20C. Excess crotonic anhydride is then decomposed by the addition of hot water and the aqueous mixture is extracted with petroleum ether. The extract is first washed with water and subsequently with 10% sodium carbonate solution until neutral. The solvent is removed by distillation under vacuum and the product is subjected to fractional vacuum distillation. There is thus obtained in this manner 41 g (74% of the theoretical calculated with respect to the unsaturated hydrocarbon) of trans-2,4,4-trimethyll-crotony1-cyc1ohex-2-ene; b.p. 86C/1 torr, d," 0.9247, n 1.4902.

EXAMPLE 2 Production of trans-2 ,3 ,4 ,4-tetramethyl-l -crotonyl-cyclohex-2-ene 69 g of l,5,5,-tetramethylcyclohex-lene are added dropwise under stirring at 10 C to a mixture of 77 g of crotonic anhydride and 10 g of tin tetrachloride. The reaction mixture is then stirred for an additional 12 hours and the excess acid anhydride is decomposed EXAMPLE 3 Production of trans-2 ,4 ,4-trimethyl-3-ethyl- 1 -crotonyl-cyclohex- 2-ene 76 g of l,5,5-trimethyl-6-ethyl-cyclohex-l-ene are added dropwise under stirring to a mixture of 77 g of crotonic anhydride and 14 g of BF -etherate, which is then stirred for an additional 10 hours at 35C. There is obtained after extraction with petroleum ether a crude product which after fractional distillation under vacuum amounts to 40.5 g (60% of the theoretical calculated with respect to the unsaturated hydrocarbon) of the above compound; b.p. ll2C/l torr, d 0.9324, n 1.4992.

EXAMPLE 4 Production of artificial fruit aroma An artificial fruit aroma is produced of the following components:

g of trans-2,4,4-trimethyl-l-crotonyl-cyclohex- 2-ene are added to 975 g of the above mixture. Odor tests carried out on this artificial fruit aroma showed that the addition of the trans-2,4,4-trimethyl-lcrotonyl-cyclohex-2-ene effects a strengthening and changing of the aroma in the direction of natural fruit aroma.

EXAMPLE 5 Production of a flower scented odoriferous composition A flower scented odoriferous composition is produced by mixing of the following components:

Component Parts by Weight Hydroxycitronellal 370 Benzylacetate 170 alpha-Amylcinnamaldehyde 100 gamma-Methylionone Phenylethylalcohol 40 Trichloromethylphenylcarbinylacetate 35 Methylnaphthylketone 30 Ylang-ylang oil extra 25 Phenylacetaldehyde, 50% solution in phthalic acid diethylester 2O Heliotropin 20 East Indian sandalwood oil 20 Vetiveryl acetate 20 lsoeugenol l5 lndole 5 gamma-Undecalacetone 5 By the addition of 50 g of trans-2,4,4-trimethyl-lcrotonyl-cyclohex-Z-ene or 50 g of trans-2,4,4,4- tetramethyll -crotonyl-cyclohex-2-ene or 50 g of trans- 2,4,4-trimethyl-3-ethyl- 1 -crotonyl-cyclohex-2-ene to 950 g of the above flowery odoriferous composition, a considerable strengthening of the diffusion is obtained. The resulting odoriferious composition moreover achieves a characteristic natural body.

While the invention has been described with respect to the use of particular compounds and particular compositions utilizing those compounds for odoriferous purposes, it is apparent that variations and modifications of the invention can be made.

What is claimed is:

1. Aroma composition comprising a perfume mixture including an aroma modifying effective amount, sufficient to enrich natural perfumes or artificial aromas, of a trans isomer of a compound of the formula: 

1. AROMA COMPOSITION COMPRISING A PERFUME MIXTURE INCLUDING AN AROMA MODIFFING EFFECTIVE AMOUNT, SUFFICIENT TO ENRICH NATUAL PERFUMES OR ARTIFICIAL AROMAS, OF A TRANS ISOMER OF A COMPOUND OF THE FORMULA:
 2. The composition of claim 1 wherein said trans isomer of said compound is present in an amount of between about 0.5-15% by weight.
 3. The composition of claim 1 wherein said trans isomer of said compound is present in an amount of about 0.03-10% by weight. 